Articulating cannula access device

ABSTRACT

Devices and methods are disclosed for less invasive surgery. More particularly, methods and devices described herein permit improved access within a body cavity when performing a minimally invasive procedure, typically through a small opening, a surgical port, or during an open surgical procedure.

FIELD OF THE INVENTIONS

Embodiments of the invention relate to methods for minimally invasivesurgery and devices useful in such methods. More particularly, methodsand devices described herein permit improved access within a body cavitywhen performing a minimally invasive procedure, typically through asmall opening or a surgical port placed in the body to provide access.In such a case, many surgical procedures require treatment of tissue ororgans that are not in alignment with an axis of the surgical opening orsurgical port. For example, ablation and/or coagulation of tissue duringminimally invasive surgical access must often be performed on tissuesurfaces that are on a posterior surface of the organ. The ability toadvance a rigid device within a body cavity and navigate the devicearound structures or organs to access a surface that would otherwise beobscured increases the ability of a physician to treat various areaswithin the body that would otherwise require an open surgical procedure.

DESCRIPTION OF THE RELATED ART

Currently, procedures that provide access to a body cavity involve smallincisions rather than creating significant openings in the body.Clearly, such minimally invasive procedures allow for reduced trauma tothe patient, reduced recuperation time, as well as reduced costs of theprocedure.

In one example, medical procedures involving the thoracic cavity requireopenings made through the chest wall. For example, such proceduresinclude median sternotomy, thoracotomy, thoracostomy, ormini-sternotomy. Typically, these surgical techniques require deflationor retraction of the lungs to access the heart and/or other organswithin the thoracic space.

A median sternotomy provides the most exposure for the physician. Inthis procedure the surgeon creates a midline incision through thesternum that cuts along the bone separating it into two sections. With amedian sternotomy, although the heart can be lifted and manipulated byhand, the posterior surface of the heart or other organs is still notreadily visible unless the heart is significantly rotated or lifted.However, significant rotation or lifting of the heart may causeundesirable hemodynamic issues during beating heart procedures. Afterthe procedure, the surgeon closes the median sternotomy with largediameter metal wires. The rejoined tissue must be held stable during thehealing process, similar to a bone fracture that must remain immobileduring rehabilitation. Any coughing or dramatic movement is extremelypainful to the patient because the chest moves. Clearly, rehabilitationafter the medial sternotomy requires a significant amount of time.

Thoracotomy techniques involve creating large (or small withminithoracotomy) incisions between the ribs to gain access to thethoracic cavity. After the incision, the surgeon separates the ribs witha rib spreader to produce space for insertion of various instruments.The muscles that overlay the chest must be cut during the thoracotomy.Much of the pain during the rehabilitation process is due to the cuttingof the muscles. A thoracotomy provides limited access and visualizationto the heart unless endoscopes are used. Yet, even the use of endoscopesprovides limited access to the posterior regions of the heart and lungsbecause these organs cannot be lifted or rotated easily.

Thoracostomy techniques use ports through the space created during thethoracotomy. The surgeon uses trocars (e.g. 6-10 mm) to access thethoracic cavity. Access to the anterior surface of the heart isgenerally sufficient with this technique. However, this technique doesnot provide ready access or visualization of posterior regions of theheart or other organs. In other words, there is no access to tissuesurfaces or organs that are not in a line-of-sight with an axis of thetrocar.

In subxyphoid techniques, the surgeon creates an incision below thexyphoid process but above the diaphragm. This technique is common forpericardiocentesis where blood is removed from the pericardial cavityduring a pericardial effusion or tamponade. The diaphragm provides abarrier and hindrance to manipulating the heart or accessing theposterior heart surface during subxyphoid techniques. Accordingly,subxyphoid techniques are often limited to procedures that target theanterior or apical ventricular regions.

The conventional surgical techniques discussed do not provide themedical practitioner with optimal visibility of anatomic structureswithin the thoracic cavity. For example, these procedures do not providesufficient visibility for anatomic structures located along or adjacentto the posterior surface of the heart or lungs. In order to obtain suchvisibility, the patient must be placed on cardiopulmonary bypasssupport. Then the surgeon must create a large incision in the patient'schest through which the patient's heart and lungs can be lifted and/orrotated. Accordingly, surgical practitioners may be hesitant to treattissues located along or adjacent to the posterior heart or lungs duringless invasive procedures, given the inability to visually observe thetarget area. As such, minimally invasive cardiothoracic surgery has beenlimited to those anatomic structures located along the anterior surfaceof the heart.

The novel methods and devices described herein offer improved access totissue regions within the body when performing minimally invasiveprocedures through small openings or ports within the body. The devicesand methods are not limited to any particular region of the body and canbe used in a variety of anatomic regions within the body.

SUMMARY OF THE INVENTION

Methods and devices described herein provide for improved manipulationof organs and/or instruments in the body or within body cavities. Themethods and devices may allow for direct visualization if tissuesurfaces, organs, other anatomic structures that are not in direct lineof sight with the surgical opening.

In one variation, the articulating access device comprises an outercannula having a rigid proximal portion and a distal portion having aflexible section and a distal tip, a first control member coupled to theouter cannula and extending from the proximal end of the outer cannulato at least the flexible section, the first control member adapted toarticulate and maintain the distal portion at an angle relative to therigid proximal portion by bending the outer cannula at the flexiblesection, and a flexible inner cannula comprising at least one lumen andhaving a straight configuration when un-flexed and having a sufficientcolumn strength to permit axial advancement through the outer cannulawhen the distal portion of the outer cannula is straight or bent, whereadvancement of the flexible inner cannula through the outer cannularesults in a telescopic movement of the flexible inner cannula in astraight line from the distal tip of the outer cannula. In additionalvariations, the flexible inner cannula can be chosen so that it advancesin a curved path rather than a straight line.

Although the access devices illustrated below are shown without handles,variations of the devices can incorporate any number of handle designswhere such handel portions are coupled to the outer cannula to aid inplacement of the device. Such handle portions can be selected based onthe type of procedure being performed.

Variations of the access devices include a second lumen within theflexible inner cannula. The second lumen can be isolated from the mainlumen to permit advancement of an instrument or visualization devicetherethrough without disturbing instruments in the main lumen.

Variations of the access device are steerable through the use of controlmembers. In many variations, the control members are located within thebody of the device to prevent interference between the body and thecontrol members. For example, by placing the control members within awall of the outer cannula (e.g., the control member can include wires,curved tubes, or any other steering mechanism or structure that isconventionally used to steer medical devices). At minimum, the outercannula will include at least one control member to allow articulationof the distal end in at least one direction. However, any number ofcontrol members can be used with the device.

The present invention also includes methods for accessing tissuesurfaces within a body of a patient where the tissue surface is obscuredby a tissue structure. Such method include advancing an outer cannulathrough a first opening in the body of the patient, where the outercannula has a rigid portion and a distal portion, where the distalportion includes a flexible section, manipulating tissue with the rigidportion of the cannula to place the distal portion adjacent to thetissue structure, articulating the distal portion by bending of theflexible section to position a distal opening around the tissuestructure, and positioning a working lumen of a flexible inner cannulaat the tissue surface by telescopically advancing the flexible innercannula through the articulated outer cannula, where the flexible innercannula bends within the flexible section but remains straight uponadvancement from the distal opening.

The method can further include coupling a visualization system to theinner cannula. Such visualization systems include scope-type devices.These devices can be inserted into a second lumen in the inner cannulato provide visual access to the tissue surface while not interferingwith other devices located within the main lumen.

These additional tools and devices located in the main lumen can be usedto perform surgical procedures at the tissue surface.

Variations of the method also include creation of at least a secondincision in the patient to provide additional visualization or access ofthe surgical procedure.

Variations of the access device and procedures described above includecombinations of features of the various embodiments or combination ofthe embodiments themselves wherever possible.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows an example of a plurality of openings created in apatient's chest or abdomen to provide an entry point for the accessdevices described herein.

FIG. 2A illustrates a variation of an articulating access device;

FIG. 2B shows a perspective view of the device of FIG. 2A whereactuation of the control member causes the cannula to articulate at aflexible section of the distal portion;

FIG. 2C shows the device of FIG. 2B after the flexible inner cannulaadvances out of the outer cannula in a telescopic type motion;

FIGS. 2D and 2E illustrate variations of an articulating access devicehaving curved or angled rigid proximal sections;

FIG. 3A shows a perspective view of a distal portion of an accessdevice;

FIG. 3B shows a cross sectional view taken along lines 3B-3B of FIG. 3A;and

FIGS. 4A to 4C illustrates one example of an articulating access deviceused to access regions of the body not in alignment with an axis of theentry point, port, or incision.

DETAILED DESCRIPTION

Methods and devices described herein provide for improved access oforgans or tissue during minimally invasive surgery. Typically, suchsurgery involves the creation of small incisions or the use of trocarsor ports to access regions of the surgical site. However, the devicesand methods can also improve access during open surgical procedures byeliminating the need to move organs or dissect significant amounts oftissues when the target site is obscured by tissue structures in thesurgical field. For example, in the case of an open chest procedurewhere a physician accesses the thoracic cavity via a median sternotomy,the use of the devices and methods described herein allow the physicianto directly visualize the obscured sides of organs other anatomicstructures without the need for excessive manipulation of the organs ortissue structures. As noted above, the methods and devices describedherein are not limited to thoracic applications but can be used in anyanatomic region of the body.

To illustrate this FIG. 1 shows examples of placement of trocars orports 106 into the chest to provide access to the thoracic cavity. FIG.1 also show use of an additional access device 182 as described incommonly assigned U.S. application Ser. No. 11/558,417 filed Nov. 9,2006; Ser. No. 11/408,315 filed Apr. 21, 2006; Ser. No. 11/408,307 filedApr. 21, 2006; Ser. No. 11/558,417 filed Nov. 9, 2006; Ser. No.11/558,419 Nov. 9, 2006; and Ser. No. 11/737,493 filed Apr. 19, 2007(“Diaphragm Entry for Posterior Surgical Access” cases) the entirety ofeach of which is incorporated by reference. Again, the use of suchminimally invasive access point benefits the patient since the openingscause less trauma and improved recuperation times over open surgicalprocedures. The number and placement of the ports 106 illustrated areintended for illustrative purposes only. Any number of ports may bearranged as needed or as conventionally used.

FIG. 2A illustrates a variation of an articulating access device 200according to the principles of the invention. As shown, the accessdevice 200 includes an outer cannula 202 with a flexible inner cannula204 slidably located therethrough. Variations of the device 200 caninclude cannulae that are circular in cross section (as shown). Inadditional variations, the cross section can be oval, rectangular, orany other shape required by the particular application. Furthermore, theaccess device 200 can include one or more handles/hubs located on eitherthe inner cannula 204 or outer cannula 202. Such handles are well knownby those familiar with the art. For purposes of illustration, the accessdevice 200 is shown without any handles or hubs. However, suchstructures are not required and the access device can simply consist ofthe telescoping cannula assembly as shown. The device 200 can also becoupled to a visualization system 300 (e.g., an endoscope, monitor for acamera located at the distal end, or other visualization component). Inaddition, the device 200 can be coupled to any number of auxiliarycomponents (such as a vacuum source, fluid source, etc.).

The outer cannula 202 comprises a first rigid section 206. The rigidsection 206 can optionally comprise a hard outer shell. However, in anycase, the rigid section 206 is sufficiently rigid such that a physiciancan advance and manipulate the cannula remotely (from the proximal end)through a body cavity and through tissue or other organs. In such cases,the physician might need to use the rigid section 206 to move or dissectorgans to properly position the opening 210 of the cannula 202 Thedistal portion of the cannula 202 comprises a flexible section 208located proximate to the opening 210. In most variations, the rigidsection 206 of the outer cannula 202 is straight. However, the rigidsection 206 can include curved or angled profiles as required by theparticular surgical application or the target anatomy.

As discussed below, configuring an articulating device to have aflexible section 208 distal to the rigid section 206 in a distal portionof the device 200 permits repositioning of the opening 210 around tissueand other structures within the body. The rigid nature of the outercannula permits the physician to leverage the device into position(typically by manipulating the device from outside of the body through aport or small incision.) The relative movement between the flexibleinner cannula 204 and the outer cannula 202 allows the physician totelescopically advance the opening of the inner cannula 204 to thedesired target site and reach organs and surfaces that are not inalignment with the surgical opening.

In the variation shown, the distal portion of the outer cannula 202includes a rigid tip 212 adjacent to the opening 210 and distal to theflexible section 208. In alternate variations, the flexible section 208can extend through the entire distal section of the cannula 202.

The outer cannula 202 also includes one or more control members 214 thatpermit flexing or articulation of the cannula 202 at the flexiblesection 208. The control member 214 can include any steering mechanismor structure that is conventionally used to steer medical devices.However, in this variation, the control member 214 comprises a pair ofwires coupled to the distal tip 212 of the outer cannula 202. Althoughnot shown, the control member 214 can include any number of features toassist in positioning of the opening 210. For example, the controlmembers can be dial, lever, or trigger actuated with an optionalratcheting mechanism to control the articulation of the cannula 202.Clearly, the articulating access device can be combined with any numberof similar features known by those skilled in the art. For example, suchstructures are described in U.S. Pat. No. 3,470,876 to Barchilon; U.S.Pat. No. 4,690,411 to Buchbinder; U.S. Pat. No. 4,898,577 to Badger etal.; U.S. Pat. No. 4,960,134 to Webster; U.S. Pat. No. 5,325,845 toAdair; and U.S. Pat. No. 6,953,454 to Peterson et al. Each of which isincorporated by reference.

FIG. 2B shows a perspective view of the device 200 of FIG. 2A whereactuation of the control member 214 (in this variation, in the directionof arrow 216) causes the cannula 202 to articulate at a distal portion.As shown, the cannula 202 bends at the flexible section 208 so that thephysician can reposition the opening 210 of the access device 202 out ofalignment with an axis of the proximal end of the cannula 202 (and thusaway from an axis of any entry incision or trocar.) In order tooptimally navigate around tissue structures or other obstructions, thecontrol member 214 is encased within the cannula 202. Alternatively, thecontrol member 214 can be exterior to the cannula or within a passagewayof the cannula as long as operation of the control member 214 does notinterfere against tissue or structures when actuating the device 200.

FIG. 2C shows the device of FIG. 2B after the flexible inner cannula 204advances out of the opening 210 in a telescopic type motion 218 when aphysician advances the cannula 204 at a proximal end as shown by arrow220. The inner cannula 204 can be completely flexible such that it canadvance through the flexible section 208 of the outer cannula 202regardless of the direction of articulation of the outer cannula 202. Inone variation, the flexible inner cannula 204 comprises a linear shapewhen un-flexed or when in natural state. Accordingly, as the innercannula 204 advances from the opening 210, it advances in a straightline configuration. The device 200 can also be configured so thatrotation of the proximal end of the flexible cannula 204 (as shown byarrow 221) causes rotation of the distal portion of the flexible cannula204 (as shown by arrow 219). In such variations, while the flexibleinner cannula 204 is fabricated to advance through the articulated outercannula 202, the flexible inner cannula 204 will be fabricated so thatrotation of the proximal end translates into a near one-to-one rotationof the distal end.

FIGS. 2D and 2E illustrate variations of the articulating access device200 where the rigid proximal section 206 of the outer cannula 202 iscurved (FIG. 2D) or has a bend 207 (FIG. 2E). Naturally, any number ofcombinations of shapes for the rigid proximal section 206 is possibleand within the scope of the device described herein. In any case, theflexible inner cannula 204 accommodates the curve or bends in the rigidsection 206 and further bends to accommodate the articulation of theflexible section 208. In most variations, as the physician advances theflexible inner cannula 204 from the distal opening 210 of the outercannula 204, the flexible inner cannula 204 assumes its straightconfiguration for telescopic advancement from the opening 210.

FIG. 3A shows a perspective view of a distal portion of an access device200. As illustrated, a pair of control members 214 is coupled to thedistal tip 212 of the cannula 202. In this case, the control member 214comprises wires on opposite sides of the outer cannula 202 to allowmovement in at least two directions. Clearly, any number of controlmembers is within the scope of this disclosure.

The flexible inner cannula 204 comprises a tapered opening 222 at theend of a passageway or working lumen 224 that extends through the innercannula 204. A tapered opening allows for an increased open area. Thisincrease in area is beneficial when advancing multiple devices throughthe cannula 204. Moreover, the tapered tip helps to advance the devicethrough the tissue by allowing the physician to gently dilate the tissueas the tip is inserted. The tapered tip also helps with visualization,as it allows structures that are not in line with the opening to beviewed.

The flexible inner cannula 204 can also include a second lumen 226separate from the main lumen 224. The second lumen 226 can be fluidlyisolated or may simply be a support frame that permits one or more toolsto be placed within the lumen 226 without interfering with otherinstruments that are within the main lumen 224. In the illustratedvariation, the second lumen 226 includes a flexible visualization typedevice 310 (e.g., one having a visualization element 312 and/or anillumination source 314). The visualization device 310 can comprise anendoscope type device or may be a video chip integrated within thechannel. In any case, the visualization type device 310 allows thephysician to remotely view the area adjacent to the opening of thesecond lumen 226. The visualization source 310 can be advanced with thedevice 200 or may be advanced once the device 200 is placed within thebody. Furthermore, as shown, the second lumen 226 and visualizationdevice 310 are shown to be recessed or offset from the end 222 of theinner cannula 204. This offset allows for the visualization device 310to observe other instruments that are advanced through the main lumenfor performing various surgical or diagnostic procedures. In addition,recessing the visualization device recessed reduces the chance thattissue will from wiping against the visualization device and obscure theview.)

FIG. 3B shows a cross sectional view taken along lines 3B-3B of FIG. 3A.In this variation, the main lumen 224 and second lumen 226 extendparallel to each other. However, in certain variations, the main lumenand second lumen can be coaxial. In alternate variations, the device caninclude various additional lumens (e.g., for suction, fluid delivery,delivery of therapeutics, etc.).

FIGS. 4A to 4C illustrates an example of the articulating access device200 when used to access regions of the body that are not aligned with anaxis of the entry point or port 106. These figures are for illustrativepurposes only. More importantly, although the access device 200 is shownas accessing the thoracic cavity through the chest wall 10, the device200 can be used in any anatomic region of the body. In one suchvariation, the device can be used with additional techniques to providemultiple points of access to a surgical site. For example, as taught inthe “Diaphragm Entry for Posterior Surgical Access” cases cited above,alternate devices are used to access posterior surfaces of organs withinthe thoracic cavity. Use of the articulating access device 200 inaddition provides the physician with an ability to locate additionaltissue regions that would otherwise be obscured.

As shown in FIG. 4A, a physician advances the access device 200 throughthe chest wall 10 (either through a trocar/port 106 or through anincision). The physician is able to manipulate organs due to the rigidportion of the device 200 when placing the distal portion of the deviceas desired. For example, in the illustrated variation, the rigid cannulacan be used to manipulate cardiac tissue or the diaphragm 170 whenplacing the device. As noted above, the inner cannula typically containsa visualization device (not shown). In this variation, the visualizationpermits the physician to locate the opening 222 of the inner cannula ata posterior ventricular surface 190.

FIG. 4B illustrates the state of the device 200 when the physicianactuates the control members 214 to bend the device at a flexiblesection 208 of the distal portion of the outer cannula 202. As shown,this permits the opening 222 of the inner cannula 204 to curve aroundthe heart to access a posterior ventricular surface 190.

FIG. 4C shows advancement of the opening 222 of the inner cannula 204when the physician advances the inner cannula from outside of the body.As noted above, because the inner cannula 204 is flexible, but returnsto its initial straight shape upon leaving the outer cannula 202, theopening 222 of the inner cannula 204 advances in a straight line towardsthe desired region. Again, this advancement is typically performed underindirect visualization. As shown, the opening 222 of the inner cannula204 is now located at a region that would have otherwise beeninaccessible due to the presence of organs and tissue structures withinthe body. As discussed above, the access device 200 can include alocking mechanism so that the physician can advance additionalinstruments or devices through the main lumen of the inner cannula 204to perform various medical diagnostic or procedures.

The invention contemplates use of any surgical device that may beadvanced through the access device to perform any procedure thatbenefits from having improved access as described herein. The integratedvacuum coagulation probe embodiments in commonly assigned co-pendingU.S. patent application Ser. No. 10/425,251 filed Apr. 29, 2003; Ser.No. 11/208,465 filed Aug. 18, 2005; Ser. No. 11/408,302 filed Apr. 21,2006; Ser. No. 11/558,420 filed Nov. 9, 2006; and Ser. No. 11/737,523filed Apr. 19, 2007I; U.S. Pat. No. 6,893,442; and PCT Application No.PCT/US2006/015009 filed Apr. 21, 2006 (Each of which is incorporated byreference here) are also examples of devices that can be used with theaccess devices described herein. Such probes provide examples of devicesthat allow intimate contact specifically between a soft tissue surfaceand the energy portion of the device. In those example, the electrode(s)used to transmit energy (radiofrequency or ultrasonic) is capable ofheating the soft tissue until achieving irreversible injury making thesoft tissue non-viable and unable to propagate electrical impulses,mutate, or reproduce. These integrated vacuum coagulation probeembodiments may be used with the articulating access device to coagulatesoft tissue capable of treating atrial fibrillation, ventriculartachycardia or other arrhythmia substrate, or eliminating cancers (suchas lung cancer), or other soft thoracic tissue by destroying targetcells.

In addition, these integrated vacuum coagulation devices may be used toheat soft tissue along the posterior heart surface resulting inheat-induced contraction of collagen in such tissue thereby resultingshrinking of said soft tissue. For example, heating the mitral valveannulus along the posterior atrio-ventricular groove may induceshrinking of the annulus thereby correcting mitral valve regurgitation.However, it is understood that the invention is not limited to the abovedescribed vacuum coagulation probes. Instead, any number of coagulation,ablation, or surgical devices may be used as required.

What is claimed is:
 1. A method of accessing tissue surfaces within abody of a patient where the tissue surface is obscured by a tissuestructure, the method comprising: advancing an outer cannula through afirst opening in the body of the patient, where the outer cannula has arigid portion and a distal portion, where the distal portion includes aflexible section; manipulating tissue with the rigid portion of thecannula to place the distal portion adjacent to the tissue structure;articulating the distal portion by bending of the flexible section toposition a distal opening around the tissue structure such that theouter cannula establishes a navigation path around the tissue structurefrom the first opening to the tissue surface while the tissue structurecontinues to obscure a line-of-sight path between the first opening andthe tissue surface; and positioning a working lumen of a flexible innercannula at the tissue surface by telescopically advancing the flexibleinner cannula through the articulated outer cannula, where the flexibleinner cannula has a linear shape when in a natural state and bendswithin the flexible section, where the flexible inner cannula resumesthe natural state upon exiting the distal opening such that an entirelength of the flexible inner cannula extending from the distal openingremains straight when advanced from the distal opening where the workinglumen of the flexible inner cannula establishes a working channel fromthe first opening to the tissue surface.
 2. The method of claim 1, wherethe outer cannula is inserted into the body to the thoracic cavity in agenerally straight profile.
 3. The method of claim 1, where the outercannula is inserted into the body to the thoracic cavity in a curved orangled profile.
 4. The method of claim 1, further comprising coupling avisualization system to the inner cannula.
 5. The method of claim 1,further comprising inserting a device having a scope into a second lumenin the inner cannula to provide visual access to the tissue surface. 6.The method of claim 1, where the working lumen comprises an oval-crosssection.
 7. The method of claim 1, where the inner cannula furthercomprises an aspiration lumen.
 8. The method of claim 1, where thetissue surface comprises a surface of the heart.
 9. The method of claim1, further comprising inserting at least one surgical instrument throughthe working lumen to the tissue surface.
 10. The method of claim 9,where the at least one surgical instrument comprises a plurality ofsurgical instruments.
 11. The method of claim 1, further comprisingperforming a surgical procedure on or near the tissue surface throughthe working lumen.
 12. The method of claim 11, further comprisingcreating at least a second incision in the patient to provide additionalvisualization of the surgical procedure.